Apple are unlikely to accept liability for impact damage. If you did not buy Applecare then your warranty is only valid for one year from the date of purchase. Even then, the same applies. Do you have house insurance? Some companies will insure against this, but many do not, since a notebook is a portable device thus is much more likely to 'fall of the table' than a desktop. Worth checking their policy on this. As for the repair, you'll likely have to take it in to an Apple repair shop and get a quote. Probably going to be expensive to be honest. Does it affect the computer in any other way?

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